public class StringConvert
{
	public static void main (String[] args)
	{
		String s = "This is a book";
		System.out.println("String: " + s);
		System.out.println("toLowerCase(): " + s.toLowerCase());
		System.out.println("toUpperCase(): " + s.toUpperCase());
		System.out.println("int 20 --> String: " + String.valueOf(20));
		System.out.println("long 20L --> String: " + String.valueOf(20L));
		System.out.println("float 20.0f --> String: " + String.valueOf(20.0f));
		System.out.println("double 20.0d --> String: " + String.valueOf(20.0d));
		System.out.println("char 'a' --> String: " + String.valueOf('a'));
		System.out.println("boolean true --> String: " + String.valueOf(true));
	}
}